Laser

• Type
  • Broad spectrum laser
  • Narrow spectrum or single frequency
  • Tunable laser

temperature will shift the frequency of laser.

EDFA

It is a kind of optical amplifiers. Amplify the signal before it is injected into the fiber.**

Like the amplifier in geophones, it will increase the noise level but won’t change SNR. Enable the signal to compete with other noise.

Optical Couplers

Split the signal into two signals in a pre-defined ratio. Could be reversed.

Optical circulator

There will be 3 ports in optical circulator. And:

Port 1 –> Port 2

Port 2 –> Port 3

Port 3 –> Port 1

Fiber Bragg Gratings(FBG)

I have touched it while learning physics.

Note that it could measure variation of temperature and strain.

Switch

Can connect one instrument with multiple fibers. This part is common in distributed systems.

Fiber Splice and Connecter

Must note to connect the right type or you’ll damage it.

Example

figure 3.1 from the textbook.